Re: Comparing Collections

[Thorbjoern Ravn Andersen <ravn@xxxxxxxxxx>]

James Perkins skrev:
> Thorbjorn,
> I do return the value in the second version I posted. It was an error in the
> code. In my original code I had:
>
> if (c1.size() > c2.size()) {
>   return 1;
> }
>
> if (c1.size() < c2.size() {
>   return -1;
> }
>   

But why?

Are you planning to sort lists of lists?


> I have actually no heard of Test Driven Design before. I will have to read
> about it a bit more, but my normal testing procedure seems to follow the
> basics I read about it. My first goal is to make sure it runs, then see if I
> can break it :-)
>   
Test Driven Design basically tells you to work like this when 
implementing a new facility:

*  Write a snippet calling the not-yet-existing-code and compare it to 
the result you expect.  Put the snippet in a test framework like junit.
* Run the test suite.
* See the new snippet fails as you do not have the code yet.
* Write the simplest possible code that makes all the tests pass.

Repeat doing this until all the cases you need have been implemented.

This tends to give a cleaner design since you think about USING your 
code first.  The testcases ensure that the code conforms to all your 
requiresments, and you can revamp a implementation thouroughly since you 
know that the testcases (which cover the important stuff) still pass.

I have seen a good introduction, which I cannot locate right now.  I'll 
have a look if you would like.